Error Detection in Critical Repeating Data in a Wireless Sensor System

ABSTRACT

Provided are methods, systems, and apparatus for error detection of bits of a data packet received at a receiver unit by detecting corrupted data bits.

RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) to U.S.provisional application No. 61/173,594 filed Apr. 28, 2009, entitled“Error Detection in Critical Repeating Data in a Wireless SensorSystem”, the disclosure of which is incorporated in its entirety byreference for all purposes.

BACKGROUND

Analyte, e.g., glucose monitoring systems including continuous anddiscrete monitoring systems generally include a small, lightweightbattery powered and microprocessor controlled system which is configuredto detect signals proportional to the corresponding measured glucoselevels using an electrometer. RF signals may be used to transmit thecollected data. One aspect of certain analyte monitoring systems includea transcutaneous or subcutaneous analyte sensor configuration which is,for example, at least partially positioned through the skin layer of asubject whose analyte level is to be monitored. The sensor may use a twoor three-electrode (work, reference and counter electrodes)configuration driven by a controlled potential (potentiostat) analogcircuit connected through a contact system.

An analyte sensor may be configured so that a portion thereof is placedunder the skin of the patient so as to contact analyte of the patient,and another portion or segment of the analyte sensor may be incommunication with the transmitter unit. The transmitter unit may beconfigured to transmit the analyte levels detected by the sensor over awireless communication link such as an RF (radio frequency)communication link to a receiver/monitor unit. The receiver/monitor unitmay perform data analysis, among other functions, on the receivedanalyte levels to generate information pertaining to the monitoredanalyte levels.

Transmission of control or command data over a wireless communicationlink is often constrained to occur within a substantially short timeduration. In turn, the time constraint in data communication imposeslimits on the type and size of data that may be transmitted during thetransmission time period.

SUMMARY

Devices and methods for analyte monitoring, e.g., glucose monitoring,and/or therapy management system including, for example, medicationinfusion device are provided. Embodiments include transmitting,repeating, providing, relaying or otherwise passing information from afirst location to a second, e.g., using a telemetry system such as RFtelemetry. Systems herein include continuous analyte monitoring systems,discrete analyte monitoring system, and/or therapy management systems.

These and other objects, features and advantages of the presentdisclosure will become more fully apparent from the following detaileddescription of the embodiments, the appended claims and the accompanyingdrawings.

INCORPORATION BY REFERENCE

The following patents, applications and/or publications are incorporatedherein by reference for all purposes: U.S. Pat. Nos. 4,545,382;4,711,245; 5,262,035; 5,262,305; 5,264,104; 5,320,715; 5,509,410;5,543,326; 5,593,852; 5,601,435; 5,628,890; 5,820,551; 5,822,715;5,899,855; 5,918,603; 6,071,391; 6,103,033; 6,120,676; 6,121,009;6,134,461; 6,143,164; 6,144,837; 6,161,095; 6,175,752; 6,270,455;6,284,478; 6,299,757; 6,338,790; 6,377,894; 6,461,496; 6,503,381;6,514,460; 6,514,718; 6,540,891; 6,560,471; 6,579,690; 6,591,125;6,592,745; 6,600,997; 6,605,200; 6,605,201; 6,616,819; 6,618,934;6,650,471; 6,654,625; 6,676,816; 6,730,200; 6,736,957; 6,746,582;6,749,740; 6,764,581; 6,773,671; 6,881,551; 6,893,545; 6,932,892;6,932,894; 6,942,518; 7,167,818; and 7,299,082; U.S. PublishedApplication Nos. 2004/0186365; 2005/0182306; 2007/0056858; 2007/0068807;2007/0227911; 2007/0233013; 2008/0081977; 2008/0161666; and2009/0054748; U.S. patent application Ser. Nos. 11/831,866; 11/831,881;11/831,895; 12/102,839; 12/102,844; 12/102,847; 12/102,855; 12/102,856;12/152,636; 12/152,648; 12/152,650; 12/152,652; 12/152,657; 12/152,662;12/152,670; 12/152,673; 12/363,712; 12/131,012; 12/242,823; 12/363,712;12/393,921; 12/495,709; 12/698,124; 12/699,653; 12/699,844; 12/714,439;12/761,372; and 12/761,387 and U.S. Provisional Application Ser. Nos.61/230,686 and 61/227,967.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a block diagram of a data monitoring and managementsystem for practicing one or more embodiments of the present disclosure;

FIG. 2 is a block diagram of the transmitter unit of the data monitoringand management system shown in FIG. 1 in accordance with one embodimentof the present disclosure;

FIG. 3 is a block diagram of the receiver/monitor unit of the datamonitoring and management system shown in FIG. 1 in accordance with oneembodiment of the present disclosure;

FIG. 4 is a flowchart illustrating data packet procedure includingrolling data for transmission in accordance with one embodiment of thepresent disclosure;

FIG. 5 is a flowchart illustrating data processing of the received datapacket including the rolling data in accordance with one embodiment ofthe present disclosure;

FIG. 6 is a flow chart illustrating error detection of rolling data of areceived data packet in accordance with one embodiment of the presentdisclosure;

FIG. 7 is a flow chart illustrating an alternative error detection ofrolling data of a received data packet; and

FIG. 8 is a flow chart illustrating an error detection of rolling datafrom a plurality of data packets in accordance with one embodiment ofthe present disclosure.

DETAILED DESCRIPTION

Before the present disclosure is described in additional detail, it isto be understood that this disclosure is not limited to particularembodiments described, as such may, of course, vary. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting, since the scope of the present disclosure will be limited onlyby the appended claims.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range, is encompassed within the disclosure. The upper and lowerlimits of these smaller ranges may independently be included in thesmaller ranges is also encompassed within the disclosure, subject to anyspecifically excluded limit in the stated range. Where the stated rangeincludes one or both of the limits, ranges excluding either or both ofthose included limits are also included in the disclosure.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this disclosure belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present disclosure, the preferredmethods and materials are now described. All publications mentionedherein are incorporated herein by reference to disclose and describe themethods and/or materials in connection with which the publications arecited.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include plural referents unless thecontext clearly dictates otherwise.

The publications discussed herein are provided solely for theirdisclosure prior to the filing date of the present application. Nothingherein is to be construed as an admission that the present disclosure isnot entitled to antedate such publication by virtue of prior disclosure.Further, the dates of publication provided may be different from theactual publication dates which may need to be independently confirmed.

As will be apparent to those of skill in the art upon reading thisdisclosure, each of the individual embodiments described and illustratedherein has discrete components and features which may be readilyseparated from or combined with the features of any of the other severalembodiments without departing from the scope or spirit of the presentdisclosure.

The figures shown herein are not necessarily drawn to scale, with somecomponents and features being exaggerated for clarity.

As summarized above and as described in further detail below, inaccordance with the various embodiments of the present disclosure, thereis provided a method and system for positioning a controller unit withina transmission range for close proximity communication, transmitting oneor more predefined close proximity commands, and receiving a responsepacket in response to the transmitted one or more predefined closeproximity commands. For example, in one aspect, close proximitycommunication includes short range wireless communication betweencommunication components or devices, where the communication range islimited to about 10 inches or less, about 5 inches or less, or about 2inches or less, or other suitable, short range distance between thedevices. The close proximity wireless communication in certainembodiments includes a bi-directional communication where a commandsending communication device, when positioned within the shortcommunication range or in close proximity to the command receivingcommunication device, is configured to transmit one or more commands tothe command receiving communication device (for example, when a useractivates or actuates a transmit command button or switch). In response,the command receiving communication device may be configured to performone or more routines associated with the received command, and/or returnor send back a response data packet or signal to the command sendingcommunication device. Example of such functions and or commands mayinclude, but not limted to activation of certain functions or routinessuch as analyte related data processing, and the like.

FIG. 1 illustrates a data monitoring and management system such as, forexample, analyte (e.g., glucose) monitoring system 100 in accordancewith one embodiment of the present disclosure. The subject invention isfurther described primarily with respect to a glucose monitoring systemfor convenience and such description is in no way intended to limit thescope of the invention. It is to be understood that the analytemonitoring system may be configured to monitor a variety of analytes,e.g., lactate, and the like.

Analytes that may be monitored include, for example, acetyl choline,amylase, bilirubin, cholesterol, chorionic gonadotropin, creatine kinase(e.g., CK-MB), creatine, DNA, fructosamine, glucose, glutamine, growthhormones, hormones, ketones, lactate, peroxide, prostate-specificantigen, prothrombin, RNA, thyroid stimulating hormone, and troponin.The concentration of drugs, such as, for example, antibiotics (e.g.,gentamicin, vancomycin, and the like), digitoxin, digoxin, drugs ofabuse, theophylline, and warfarin, may also be monitored. More than oneanalyte may be monitored by a single system, e.g. a single analytesensor.

The analyte monitoring system 100 includes a sensor unit 101, atransmitter unit 102 coupleable to the sensor unit 101, and a primaryreceiver unit 104 which is configured to communicate with thetransmitter unit 102 via a bi-directional communication link 103. Theprimary receiver unit 104 may be further configured to transmit data toa data processing terminal 105 for evaluating the data received by theprimary receiver unit 104. Moreover, the data processing terminal 105 inone embodiment may be configured to receive data directly from thetransmitter unit 102 via a communication link which may optionally beconfigured for bi-directional communication. Accordingly, transmitterunit 102 and/or receiver unit 104 may include a transceiver.

Also shown in FIG. 1 is an optional secondary receiver unit 106 which isoperatively coupled to the communication link 103 and configured toreceive data transmitted from the transmitter unit 102. Moreover, asshown in the Figure, the secondary receiver unit 106 is configured tocommunicate with the primary receiver unit 104 as well as the dataprocessing terminal 105. Indeed, the secondary receiver unit 106 may beconfigured for bi-directional wireless communication with each or one ofthe primary receiver unit 104 and the data processing terminal 105. Asdiscussed in further detail below, in one embodiment of the presentdisclosure, the secondary receiver unit 106 may be configured to includea limited number of functions and features as compared with the primaryreceiver unit 104. As such, the secondary receiver unit 106 may beconfigured substantially in a smaller compact housing or embodied in adevice such as a wrist watch, pager, mobile phone, PDA, for example.Alternatively, the secondary receiver unit 106 may be configured withthe same or substantially similar functionality as the primary receiverunit 104. The receiver unit may be configured to be used in conjunctionwith a docking cradle unit, for example for one or more of the followingor other functions: placement by bedside, for re-charging, for datamanagement, for night time monitoring, and/or bi-directionalcommunication device.

In one aspect sensor unit 101 may include two or more sensors, eachconfigured to communicate with transmitter unit 102. Furthermore, whileonly one, transmitter unit 102, communication link 103, and dataprocessing terminal 105 are shown in the embodiment of the analytemonitoring system 100 illustrated in FIG. 1. However, it will beappreciated by one of ordinary skill in the art that the analytemonitoring system 100 may include one or more sensors, multipletransmitter units 102, communication links 103, and data processingterminals 105. Moreover, within the scope of the present disclosure, theanalyte monitoring system 100 may be a continuous monitoring system, orsemi-continuous, or a discrete monitoring system. In a multi-componentenvironment, each device is configured to be uniquely identified by eachof the other devices in the system so that communication conflict isreadily resolved between the various components within the analytemonitoring system 100.

In one embodiment of the present disclosure, the sensor unit 101 isphysically positioned in or on the body of a user whose analyte level isbeing monitored. The sensor unit 101 may be configured to continuouslysample the analyte level of the user and convert the sampled analytelevel into a corresponding data signal for transmission by thetransmitter unit 102. In certain embodiments, the transmitter unit 102may be physically coupled to the sensor unit 101 so that both devicesare integrated in a single housing and positioned on the user's body.The transmitter unit 102 may perform data processing such as filteringand encoding on data signals and/or other functions, each of whichcorresponds to a sampled analyte level of the user, and in any eventtransmitter unit 102 transmits analyte information to the primaryreceiver unit 104 via the communication link 103. Examples of suchintegrated sensor and transmitter units can be found in, among others,U.S. patent application Ser. No. 12/698,124, incorporated herein byreference.

In one embodiment, the analyte monitoring system 100 is configured as aone-way RF communication path from the transmitter unit 102 to theprimary receiver unit 104. In such embodiment, the transmitter unit 102transmits the sampled data signals received from the sensor unit 101without acknowledgement from the primary receiver unit 104 that thetransmitted sampled data signals have been received. For example, thetransmitter unit 102 may be configured to transmit the encoded sampleddata signals at a fixed rate (e.g., at one minute intervals) after thecompletion of the initial power on procedure. Likewise, the primaryreceiver unit 104 may be configured to detect such transmitted encodedsampled data signals at predetermined time intervals. Alternatively, theanalyte monitoring system 100 may be configured with a bi-directional RF(or otherwise) communication between the transmitter unit 102 and theprimary receiver unit 104.

Additionally, in one aspect, the primary receiver unit 104 may includetwo sections. The first section is an analog interface section that isconfigured to communicate with the transmitter unit 102 via thecommunication link 103. In one embodiment, the analog interface sectionmay include an RF receiver and an antenna for receiving and amplifyingthe data signals from the transmitter unit 102, which are thereafter,demodulated with a local oscillator and filtered through a band-passfilter. The second section of the primary receiver unit 104 is a dataprocessing section which is configured to process the data signalsreceived from the transmitter unit 102 such as by performing datadecoding, error detection and correction, data clock generation, anddata bit recovery.

In operation, upon completing the power-on procedure, the primaryreceiver unit 104 is configured to detect the presence of thetransmitter unit 102 within its range based on, for example, thestrength of the detected data signals received from the transmitter unit102 and/or a predetermined transmitter identification information. Uponsuccessful synchronization with the corresponding transmitter unit 102,the primary receiver unit 104 is configured to begin receiving from thetransmitter unit 102 data signals corresponding to the user's detectedanalyte level. More specifically, the primary receiver unit 104 in oneembodiment is configured to perform synchronized time hopping with thecorresponding synchronized transmitter unit 102 via the communicationlink 103 to obtain the user's detected analyte level.

Referring again to FIG. 1, the data processing terminal 105 may includea personal computer, a portable computer such as a laptop or a handhelddevice (e.g., personal digital assistants (PDAs)), and the like, each ofwhich may be configured for data communication with the receiver via awired or a wireless connection. Additionally, the data processingterminal 105 may further be connected to a data network (not shown) forstoring, retrieving and updating data corresponding to the detectedanalyte level of the user.

Within the scope of the present disclosure, the data processing terminal105 may include an infusion device such as an insulin infusion pump(external or implantable) or the like, which may be configured toadminister insulin to patients, and which may be configured tocommunicate with the receiver unit 104 for receiving, among others, themeasured analyte level. Alternatively, the receiver unit 104 may beconfigured to integrate or otherwise couple to an infusion devicetherein so that the receiver unit 104 is configured to administerinsulin therapy to patients, for example, for administering andmodifying basal profiles, as well as for determining appropriate bolusesfor administration based on, among others, the detected analyte levelsreceived from the transmitter unit 102.

Additionally, the transmitter unit 102, the primary receiver unit 104and the data processing terminal 105 may each be configured forbi-directional wireless communication such that each of the transmitterunit 102, the primary receiver unit 104 and the data processing terminal105 may be configured to communicate (that is, transmit data to andreceive data from) with each other via the wireless communication link103. More specifically, the data processing terminal 105 may in oneembodiment be configured to receive data directly from the transmitterunit 102 via the communication link 103, where the communication link103, as described above, may be configured for bi-directionalcommunication.

In this embodiment, the data processing terminal 105 which may includean insulin pump, may be configured to receive the analyte signals fromthe transmitter unit 102, and thus, incorporate the functions of thereceiver 104 including data processing for managing the patient'sinsulin therapy and analyte monitoring. In one embodiment, thecommunication link 103 may include one or more of an RF communicationprotocol, an infrared communication protocol, a Bluetooth® enabledcommunication protocol, an 802.11x wireless communication protocol, oran equivalent wireless communication protocol which would allow secure,wireless communication of several units (for example, per HIPPArequirements) while avoiding potential data collision and interference.

FIG. 2 is a block diagram of the transmitter of the data monitoring anddetection system shown in FIG. 1 in accordance with one embodiment ofthe present disclosure. Referring to the Figure, the transmitter unit102 in one embodiment includes an analog interface 201 configured tocommunicate with the sensor unit 101 (FIG. 1), a user input 202, and atemperature measurement section 203, each of which is operativelycoupled to a transmitter processor 204 such as a central processing unit(CPU). As can be seen from FIG. 2, there are provided four contacts,three of which are electrodes—work electrode (W) 210, guard contact (G)211, reference electrode (R) 212, and counter electrode (C) 213, eachoperatively coupled to the analog interface 201 of the transmitter unit102 for connection to the sensor unit 101 (FIG. 1). In one embodiment,each of the work electrode (W) 210, guard contact (G) 211, referenceelectrode (R) 212, and counter electrode (C) 213 may be made using aconductive material that is either printed or etched or ablated, forexample, such as carbon which may be printed, or a metal such as a metalfoil (e.g., gold) or the like, which may be etched or ablated orotherwise processed to provide one or more electrodes. Fewer or greaterelectrodes and/or contact may be provided in certain embodiments.

Further shown in FIG. 2 are a transmitter serial communication section205 and an RF transmitter 206, each of which is also operatively coupledto the transmitter processor 204. Moreover, a power supply 207 such as abattery is also provided in the transmitter unit 102 to provide thenecessary power for the transmitter unit 102. In certain embodiments,the power supply 207 also provides the power necessary to power thesensor 101. In other embodiments, the sensor is a self-powered sensor,such as the sensor described in U.S. patent application Ser. No.12/393,921, incorporated herein by reference. Additionally, as can beseen from the Figure, clock 208 is provided to, among others, supplyreal time information to the transmitter processor 204.

In one embodiment, a unidirectional input path is established from thesensor unit 101 (FIG. 1) and/or manufacturing and testing equipment tothe analog interface 201 of the transmitter unit 102, while aunidirectional output is established from the output of the RFtransmitter 206 of the transmitter unit 102 for transmission to theprimary receiver unit 104 (FIG. 1). In this manner, a data path is shownin FIG. 2 between the aforementioned unidirectional input and output viaa dedicated link 209 from the analog interface 201 to serialcommunication section 205, thereafter to the processor 204, and then tothe RF transmitter 206. As such, in one embodiment, via the data pathdescribed above, the transmitter unit 102 is configured to transmit tothe primary receiver unit 104, via the communication link 103 (FIG. 1),processed and encoded data signals received from the sensor unit 101.Additionally, the unidirectional communication data path between theanalog interface 201 and the RF transmitter 206 discussed above allowsfor the configuration of the transmitter unit 102 for operation uponcompletion of the manufacturing process as well as for directcommunication for diagnostic and testing purposes.

As discussed above, the transmitter processor 204 is configured totransmit control signals to the various sections of the transmitter unit102 during the operation of the transmitter unit 102. In one embodiment,the transmitter processor 204 also includes a memory (not shown) forstoring data such as the identification information for the transmitterunit 102, as well as the data signals received from the sensor unit 101(FIG. 1). The stored information may be retrieved and processed fortransmission to the primary receiver unit 104 under the control of thetransmitter processor 204. Furthermore, the power supply 207 may includea commercially available battery, which may be a rechargeable battery.

In certain embodiments, the transmitter unit 102 is also configured suchthat the power supply section 207 is capable of providing power to thetransmitter for a minimum of about three months of continuous operation,e.g., after having been stored for about eighteen months such as storedin a low-power (non-operating) mode. In one embodiment, this may beachieved by the transmitter processor 204 operating in low power modesin the non-operating state, for example, drawing no more thanapproximately 1 μA of current. Indeed, in one embodiment, a step duringthe manufacturing process of the transmitter unit 102 may place thetransmitter unit 102 in the lower power, non-operating state (i.e.,post-manufacture sleep mode). In this manner, the shelf life of thetransmitter unit 102 may be significantly improved. Moreover, as shownin FIG. 2, while the power supply unit 207 is shown as coupled to theprocessor 204, and as such, the processor 204 is configured to providecontrol of the power supply unit 207, it should be noted that within thescope of the present disclosure, the power supply unit 207 is configuredto provide the necessary power to each of the components of thetransmitter unit 102 shown in FIG. 2.

Referring back to FIG. 2, the power supply section 207 of thetransmitter unit 102 in one embodiment may include a rechargeablebattery unit that may be recharged by a separate power supply rechargingunit (for example, provided in the receiver unit 104) so that thetransmitter unit 102 may be powered for a longer period of usage time.Moreover, in one embodiment, the transmitter unit 102 may be configuredwithout a battery in the power supply section 207, in which case thetransmitter unit 102 may be configured to receive power from an externalpower supply source (for example, a battery) as discussed in furtherdetail below.

Referring yet again to FIG. 2, the temperature measurement section 203of the transmitter unit 102 is configured to monitor the temperature ofthe skin near the sensor insertion site. The temperature reading is usedto adjust the analyte readings obtained from the analog interface 201.In certain embodiments, the RF transmitter 206 of the transmitter unit102 may be configured for operation in the frequency band ofapproximately 315 MHz to approximately 322 MHz, for example, in theUnited States. In certain embodiments, the RF transmitter 206 of thetransmitter unit 102 may be configured for operation in the frequencyband of approximately 400 MHz to approximately 470 MHz. Further, in oneembodiment, the RF transmitter 206 is configured to modulate the carrierfrequency by performing Frequency Shift Keying and Manchester encoding.In one embodiment, the data transmission rate is about 19,200 symbolsper second, with a minimum transmission range for communication with theprimary receiver unit 104.

Referring yet again to FIG. 2, also shown is a leak detection circuit214 coupled to the guard electrode (G) 211 and the processor 204 in thetransmitter unit 102 of the data monitoring and management system 100.The leak detection circuit 214 in accordance with one embodiment of thepresent disclosure may be configured to detect leakage current in thesensor unit 101 to determine whether the measured sensor data arecorrupt or whether the measured data from the sensor 101 is accurate.Exemplary analyte systems that may be employed are described in, forexample, U.S. Pat. Nos. 6,134,461, 6,175,752, 6,121,611, 6,560,471,6,746,582, and elsewhere, the disclosure of each of which areincorporated by reference for all purposes.

FIG. 3 is a block diagram of the receiver/monitor unit of the datamonitoring and management system shown in FIG. 1 in accordance with oneembodiment of the present disclosure. Referring to FIG. 3, the primaryreceiver unit 104 includes an analyte test strip, e.g., blood glucosetest strip, interface 301, an RF receiver 302, an input 303, atemperature monitor section 304, and a clock 305, each of which isoperatively coupled to a receiver processor 307. As can be further seenfrom the Figure, the primary receiver unit 104 also includes a powersupply 306 operatively coupled to a power conversion and monitoringsection 308. Further, the power conversion and monitoring section 308 isalso coupled to the receiver processor 307. Moreover, also shown are areceiver serial communication section 309, and an output 310, eachoperatively coupled to the receiver processor 307.

In one embodiment, the test strip interface 301 includes a glucose leveltesting portion to receive a manual insertion of a glucose test strip,and thereby determine and display the glucose level of the test strip onthe output 310 of the primary receiver unit 104. This manual testing ofglucose may be used to calibrate the sensor unit 101 or otherwise. TheRF receiver 302 is configured to communicate, via the communication link103 (FIG. 1) with the RF transmitter 206 (FIG. 2) of the transmitterunit 102, to receive encoded data signals from the transmitter unit 102for, among others, signal mixing, demodulation, and other dataprocessing. The input 303 of the primary receiver unit 104 is configuredto allow the user to enter information into the primary receiver unit104 as needed. In one aspect, the input 303 may include one or more keysof a keypad, a touch-sensitive screen, or a voice-activated inputcommand unit. The temperature monitor section 304 is configured toprovide temperature information of the primary receiver unit 104 to thereceiver processor 307, while the clock 305 provides, among others, realtime information to the receiver processor 307.

Each of the various components of the primary receiver unit 104 shown inFIG. 3 is powered by the power supply 306 which, in one embodiment,includes a battery. Furthermore, the power conversion and monitoringsection 308 is configured to monitor the power usage by the variouscomponents in the primary receiver unit 104 for effective powermanagement and to alert the user, for example, in the event of powerusage which renders the primary receiver unit 104 in sub-optimaloperating conditions. An example of such sub-optimal operating conditionmay include, for example, operating the vibration output mode (asdiscussed below) for a period of time thus substantially draining thepower supply 306 while the processor 307 (thus, the primary receiverunit 104) is turned on. Moreover, the power conversion and monitoringsection 308 may additionally be configured to include a reverse polarityprotection circuit such as a field effect transistor (FET) configured asa battery activated switch.

The serial communication section 309 in the primary receiver unit 104 isconfigured to provide a bi-directional communication path from thetesting and/or manufacturing equipment for, among others,initialization, testing, and configuration of the primary receiver unit104. Serial communication section 104 can also be used to upload data toa computer, such as time-stamped blood glucose data. The communicationlink with an external device (not shown) can be made, for example, bycable, infrared (IR) or RF link. The output 310 of the primary receiverunit 104 is configured to provide, among others, a graphical userinterface (GUI) such as a liquid crystal display (LCD) for displayinginformation. Additionally, the output 310 may also include an integratedspeaker for outputting audible signals as well as to provide vibrationoutput as commonly found in handheld electronic devices, such as mobiletelephones presently available. In a further embodiment, the primaryreceiver unit 104 also includes an electro-luminescent lamp configuredto provide backlighting to the output 310 for output visual display indark ambient surroundings.

Referring back to FIG. 3, the primary receiver unit 104 in oneembodiment may also include a storage section such as a programmable,non-volatile memory device as part of the processor 307, or providedseparately in the primary receiver unit 104, operatively coupled to theprocessor 307. The processor 307 may be configured to synchronize with atransmitter, e.g., using Manchester decoding or the like, as well aserror detection and correction upon the encoded data signals receivedfrom the transmitter unit 102 via the communication link 103.

Additional description of the RF communication between the transmitter102 and the primary receiver 104 (or with the secondary receiver 106)that may be employed in embodiments of the subject invention isdisclosed in pending application Ser. No. 11/060,365 filed Feb. 16, 2005entitled “Method and System for Providing Data Communication inContinuous Glucose Monitoring and Management System” the disclosure ofwhich is incorporated herein by reference for all purposes.

Referring to the Figures, in one embodiment, the transmitter 102(FIG. 1) may be configured to generate data packets for periodictransmission to one or more of the receiver units 104, 106, where eachdata packet includes in one embodiment two categories of data—urgentdata and non-urgent data. For example, urgent data such as for exampleglucose data from the sensor and/or temperature data associated with thesensor may be packed in each data packet in addition to non-urgent data,where the non-urgent data is rolled or varied with each data packettransmission.

That is, the non-urgent data is transmitted at a timed interval so as tomaintain the integrity of the analyte monitoring system without beingtransmitted over the RF communication link with each data transmissionpacket from the transmitter 102. In this manner, the non-urgent data,for example the data that is not time sensitive, may be periodicallytransmitted (and not with each data packet transmission) or broken upinto predetermined number of segments and sent or transmitted overmultiple packets, while the urgent data is transmitted substantially inits entirety with each data transmission.

Referring again to the Figures, upon receiving the data packets from thetransmitter 102, the one or more receiver units 104, 106 may beconfigured to parse the received data packet to separate the urgent datafrom the non-urgent data, and also, may be configured to store theurgent data and the non-urgent data, e.g., in a hierarchical manner. Inaccordance with the particular configuration of the data packet or thedata transmission protocol, more or less data may be transmitted as partof the urgent data, or the non-urgent rolling data. That is, within thescope of the present disclosure, the specific data packet implementationsuch as the number of bits per packet, and the like, may vary based on,among others, the communication protocol, data transmission time window,and so on.

In an exemplary embodiment, different types of data packets may beidentified accordingly. For example, identification in certain exemplaryembodiments may include—(1) single sensor, one minute of data, (2) twoor multiple sensors, (3) dual sensor, alternate one minute data, and (4)response packet. For single sensor one minute data packet, in oneembodiment, the transmitter 102 may be configured to generate the datapacket in the manner, or similar to the manner, shown in Table 1 below.

TABLE 1 Single sensor, one minute of data Number of Bits Data Field 8Rolling-Data-1 12 AUX Thermistor 1 12 AUX Thermistor 2 8 Transmit Time12 AUX Counter 14 Sensor1 Current Data 14 Sensor1 Historic Data 8Transmitter Status

As shown in Table 1 above, the transmitter data packet in one embodimentmay include 8 bits of rolling data, 12 bits of auxiliary counter data,12 bits of auxiliary thermistor 1 data, 12 bits of auxiliary thermistor2 data, 14 bits of current sensor data, 14 bits of preceding sensordata, 8 bits of transmit time data, and 8 bits of transmitter statusdata. In one embodiment of the present disclosure, the data packetgenerated by the transmitter for transmission over the RF communicationlink may include all or some of the data shown above in Table 1.

Referring back, the 14 bits of the current sensor data provides the realtime or current sensor data associated with the detected analyte level,while the 14 bits of the sensor historic or preceding sensor dataincludes the sensor data associated with the detected analyte level oneminute ago. In this manner, in the case where the receiver unit 104, 106drops or fails to successfully receive the data packet from thetransmitter 102 in the minute by minute transmission, the receiver unit104, 106 may be able to capture the sensor data of a prior minutetransmission from a subsequent minute transmission.

Referring again to Table 1, the auxiliary data in one embodiment mayinclude one or more of the patient's skin temperature data, atemperature gradient data, reference data, and counter electrodevoltage. The transmitter status field may include status data that isconfigured to indicate corrupt data for the current transmission (forexample, if shown as BAD status (as opposed to GOOD status whichindicates that the data in the current transmission is not corrupt)).Furthermore, the rolling data field is configured to include thenon-urgent data, and in one embodiment, may be associated with thetime-hop sequence number. In addition, the transmitter time field in oneembodiment includes a protocol value that is configured to start at zeroand is incremented by one with each data packet. In one aspect, thetransmitter time data may be used to synchronize the data transmissionwindow with the receiver unit 104, 106 (FIG. 1), and also, provide anindex for the rolling data field.

In a further embodiment, the transmitter data packet may be configuredto provide or transmit analyte sensor data from two or more independentanalyte sensors. The sensors may relate to the same or different analyteor property. In such a case, the data packet from the transmitter 102may be configured to include 14 bits of the current sensor data fromboth sensors in the embodiment in which 2 sensors are employed, as shownin Table 2 below. In this case, the data packet does not include theimmediately preceding sensor data in the current data packettransmission. Instead, a second analyte sensor data is transmitted witha first analyte sensor data.

TABLE 2 Dual sensor data Number of Bits Data Field 8 Rolling-Data-1 12AUX Thermistor 1 12 AUX Thermistor 2 8 Transmit Time 12 AUX Counter 14Sensor1 Current Data 14 Sensor2 Current Data 8 Transmitter Status

In a further embodiment, the transmitter data packet may be alternatedwith each transmission between two analyte sensors, for example,alternating between the data packet shown in Table 3 and Table 4 below.

TABLE 3 Sensor Data Packet Alternate 1 Number of Bits Data Field 8Rolling-Data-1 12 AUX Thermistor 1 12 AUX Thermistor 2 8 Transmit Time12 AUX Counter 14 Sensor1 Current Data 14 Sensor1 Historic Data 8Transmitter Status

TABLE 4 Sensor Data Packet Alternate 2 Number of Bits Data Field 8Rolling-Data-1 12 AUX Thermistor 1 12 AUX Thermistor 2 8 Transmit Time12 AUX Counter 14 Sensor1 Current Data 14 Sensor2 Current Data 8Transmitter Status

As shown above in reference to Tables 3 and 4, the minute by minute datapacket transmission from the transmitter 102 (FIG. 1) in one embodimentmay alternate between the data packet shown in Table 3 and the datapacket shown in Table 4. More specifically, the transmitter 102 may beconfigured in one embodiment to transmit the current sensor data of thefirst sensor and the preceding sensor data of the first sensor (Table3), as well as the rolling data, and further, at the subsequenttransmission, the transmitter 102 may be configured to transmit thecurrent sensor data of the first and the second sensor in addition tothe rolling data (Table 4).

In one embodiment, the rolling data transmitted with each data packetmay include a sequence of various predetermined types of data that areconsidered not-urgent or not time sensitive. That is, in one embodiment,the following list of data shown in Table 5 may be sequentially includedin the 8 bits of transmitter data packet, and not transmitted with eachdata packet transmission of the transmitter (for example, with each 60second data transmission from the transmitter 102).

TABLE 5 Rolling Data Time Slot Bits Rolling-Data 0 8 Counter, Ref-R 1 8Counter 2 8 Counter 3 8 Sensor Count 4 8 Mode 5 8 Glucose1 Slope 6 8Glucose2 Slope 7 8 Ref-R

As can be seen from Table 5 above, in one embodiment, a sequence ofrolling data are appended or added to the transmitter data packet witheach data transmission time slot. In one embodiment, there may be 256time slots for data transmission by the transmitter 102 (FIG. 1), andwhere, each time slot is separated by approximately 60 second interval.For example, referring to the Table 5 above, the data packet intransmission time slot 0 (zero) may include operational mode data (Mode)as the rolling data that is appended to the transmitted data packet. Atthe subsequent data transmission time slot (for example, approximately60 seconds after the initial time slot (0)), the transmitted data packetmay include the analyte sensor 1 calibration factor information(Glucose1 slope) as the rolling data. In this manner, with each datatransmission, the rolling data may be updated over the 256 time slotcycle.

Referring again to Table 5, each rolling data field is described infurther detail for various embodiments. For example, the Mode data mayinclude information related to the different operating modes such as,but not limited to, the data packet type, the type of battery used,diagnostic routines, single sensor or multiple sensor input, or type ofdata transmission (RF communication link or other data link such asserial connection). Further, the Glucose1-slope data may include an8-bit scaling factor or calibration data for first sensor (scalingfactor for sensor 1 data), while Glucose2-slope data may include an8-bit scaling factor or calibration data for the second analyte sensor(in the embodiment including more than one analyte sensors).

In addition, the Ref-R data may include 12 bits of on-board referenceresistor used to calibrate the temperature measurement in the thermistorcircuit (where 8 bits are transmitted in time slot 3, and the remaining4 bits are transmitted in time slot 4), and the 20-bit counter data maybe separately transmitted in three time slots (for example, in time slot4, time slot 5 and time slot 6) to add up to 20 bits. In one embodiment,the counter may be configured to count each occurrence of the datatransmission (for example, a packet transmission at approximately 60second intervals) and may be incremented by a count of one (1).

In one aspect, the counter is stored in a nonvolatile memory of thetransmitter unit 102 (FIG. 1) and may be used to ascertain the powersupply status information such as, for example, the estimated batterylife remaining in the transmitter unit 102. That is, with each sensorreplacement, the counter is not reset, but rather, continues the countwith each replacement of the sensor unit 101 to establish contact withthe transmitter unit 102 such that, over an extended usage time periodof the transmitter unit 102, it may be possible to determine, based onthe count information, the amount of consumed battery life in thetransmitter unit 102, and also, an estimated remaining life of thebattery in the transmitter unit 102.

Referring to Table 5 above, the transmitted rolling data may alsoinclude 8 bits of sensor count information (for example, transmitted intime slot 7). The 8 bit sensor counter is incremented by one each time anew sensor unit is connected to the transmitter unit. The ASICconfiguration of the transmitter unit (or a microprocessor basedtransmitter configuration or with discrete components) may be configuredto store in a nonvolatile memory unit the sensor count information andtransmit it to the primary receiver unit 104 (for example). In turn, theprimary receiver unit 104 (and/or the secondary receiver unit 106) maybe configured to determine whether it is receiving data from thetransmitter unit that is associated with the same sensor unit (based onthe sensor count information), or from a new or replaced sensor unit(which will have a sensor count incremented by one from the prior sensorcount). In this manner, in one aspect, the receiver unit (primary orsecondary) may be configured to prevent reuse of the same sensor unit bythe user based on verifying the sensor count information associated withthe data transmission received from the transmitter unit 102. Inaddition, in a further aspect, user notification may be associated withone or more of these parameters. Further, the receiver unit (primary orsecondary) may be configured to detect when a new sensor has beeninserted, and thus prevent erroneous application of one or morecalibration parameters determined in conjunction with a prior sensor,that may potentially result in false or inaccurate analyte leveldetermination based on the sensor data.

FIG. 4 is a flowchart illustrating a data packet procedure includingrolling data for transmission in accordance with one embodiment of thepresent disclosure. Referring to FIG. 4, in one embodiment, a counter isinitialized (for example, to T=0) (410). Thereafter the associatedrolling data is retrieved from memory device, for example (420), andalso, the time sensitive or urgent data is retrieved (430). In oneembodiment, the retrieval of the rolling data (420) and the retrieval ofthe time sensitive data (430) may be retrieved at substantially the sametime.

Referring back to FIG. 4, with the rolling data and the time sensitivedata, for example, the data packet for transmission is generated (440),and upon transmission, the counter is incremented by one (450) and theroutine returns to retrieval of the rolling data (420). In this manner,in one embodiment, the urgent time sensitive data as well as thenon-urgent data may be incorporated in the same data packet andtransmitted by the transmitter 102 (FIG. 1) to a remote device such asone or more of the receivers 104, 106. Furthermore, as discussed above,the rolling data may be updated at a predetermined time interval whichis longer than the time interval for each data packet transmission fromthe transmitter 102 (FIG. 1).

FIG. 5 is a flowchart illustrating data processing of the received datapacket including the rolling data in accordance with one embodiment ofthe present disclosure. Referring to FIG. 5, when the data packet isreceived (510) (for example, by one or more of the receivers 104, 106,in one embodiment) the received data packet is parsed so that the urgentdata may be separated from the not-urgent data (stored in, for example,the rolling data field in the data packet) (520). Thereafter the parseddata is suitably stored in an appropriate memory or storage device(530).

In one or more embodiments of the present disclosure, data transmissionerrors may occur in the data packets received by a receiver unit, forexample, by the primary receiver unit 104 (FIG. 1). In certain aspects,failure to detect a corrupt data packet resulting from, for example, atransmission error, can have a substantial effect. For example, in thecase of calibration data, an undetected corrupt data packet may includea value which will be applied to every data point to be calibrated. Assuch, the effect of the single corrupted data value will be multipliedand thus its undesirable effect magnified. Thus, it is desirable to havean approach to detect corrupt data packets, including data packetsrelated to calibration data, so that subsequent corrective measures maybe taken.

FIG. 6 is a flow chart illustrating error detection of rolling data of areceived data packet in accordance with one embodiment of the presentdisclosure. Referring to FIG. 6, a receiver unit, for example theprimary receiver unit 104 (FIG. 1) in one embodiment may be configuredto receive a data packet (610) including rolling data from a transmitter102 (FIG. 1). The data packet is parsed into rolling data and timesensitive data (620). The received rolling data is then compared topreviously stored rolling data (630) to check if the received rollingdata matches the previously stored rolling data (640).

In one aspect, if the received rolling data matches the stored rollingdata, the received rolling data is accepted (650) as valid data. Thevalid received rolling data is stored (660) for comparison to the nextreceived rolling data. If the received rolling data does not match thestored rolling data, the data is not accepted as valid, but the receivedrolling data is nevertheless stored (660) for comparison to the nextreceived rolling data in case the received rolling data is not an error,but is a valid change in the rolling data. As such, if the receivedrolling data is not an error, but is a valid change in the rolling data,the subsequently received rolling data will match the newly storedrolling data, and the receiver unit will determine the rolling data asvalid.

In other embodiments, the error detection of rolling data may requiremore than two consecutive matching rolling data values before thereceiver unit recognizes the rolling data as valid. FIG. 7 is a flowchart illustrating an alternative error detection of rolling data of areceived data packet. Referring to FIG. 7, a receiver unit, for examplethe primary receiver unit 104 (FIG. 1) receives a data packet (710)including rolling data. The data packet is parsed into rolling data andtime sensitive data (720). The received rolling data is then compared topreviously stored rolling data (730) to check if the received rollingdata matches the previously stored rolling data (740). If the receivedrolling data matches the stored rolling data, a counter is incremented(750) by one. The counter is checked against or compared to apredetermined threshold value (760), for example 2, 3, or 4 (or anyother suitable value), and if the counter is equal to or greater thanthe threshold value, the rolling data is accepted as valid (770). If thereceived rolling data does not match the stored rolling data, the storedrolling data value is replaced with the received rolling data value(780) and the counter is initialized back to one (790).

The threshold value for the counter indicating the number of consecutivetimes the rolling data matches the previous value may be any number ofvalues. The higher the threshold, the higher the probability ofdetecting a corruption in the received rolling data before the receivedrolling data is accepted as valid. However, if a threshold value isconfigured as too high a value, then the rolling data may legitimatelychange before the receiver unit determines the received rolling data isvalid.

The rolling data included in each transmitted data packet, in one ormore embodiment, may be only a portion of a set of rolling data. Forexample, the rolling data may comprise calibration data, wherein thecalibration data is comprised of 8 bytes of data. In one embodiment,each data packet contains 1 byte (8 bits) of rolling data and therefore,to transmit the entire 8 bytes of calibration data, 1 byte at a time istransmitted via 8 consecutive data packets. FIG. 8 is a flow chartillustrating an error detection of rolling data from a plurality of datapackets in accordance with one embodiment of the present disclosure.

Referring to FIG. 8, a receiver unit, for example the primary receiverunit 104 (FIG. 1) receives a first data packet (810) including rollingdata, which may be a first byte of calibration data. The data packet isparsed into rolling data and time sensitive data (820). The receivedfirst byte of calibration data is then compared to previously storedfirst byte of calibration data (830) to check if the received first byteof calibration data matches the previously stored first byte ofcalibration data (840). If the received first byte of calibration datamatches the stored first byte of calibration data, a first element orblock of a counter array is incremented (850) by one. The counter arrayis comprised of a predetermined number of elements or blockscorresponding to the number of bytes of data associated with thereceived rolling data. For example, if the rolling data is calibrationdata, and the calibration data consists of 8 bytes, the counter arrayincludes 8 elements.

Referring back to FIG. 8, each element of the counter array is checkedagainst or compared to a predetermined threshold value (860), forexample 2, 3, or 4 (or any other suitable value), and if each element ofthe counter array is equal to or greater than the threshold value, thecalibration data is accepted as valid (870). If not all the elements ofthe counter array are equal to or greater than the threshold value, thecalibration data is not accepted as valid since all bytes of thecalibration data must be verified as non-corrupt before the calibrationis considered valid. The threshold value for each element of the counterarray, which indicates the number of consecutive times each byte of thecalibration data matches the previous stored byte of calibration data,may be any number of values. The higher the threshold, the higher theprobability of detecting a corruption in the received calibration databefore the received calibration data is accepted as valid. However, if athreshold value is configured as too high a value, then the calibrationdata may legitimately change before the receiver unit determines thereceived calibration data is valid. In one aspect, once a receivedcalibration data has been accepted as valid, the receiver unit may usethe valid calibration data for comparison with received calibrationdata.

Still referring to FIG. 8, if the received first byte of calibrationdata does not match the stored first byte of calibration data, thestored first byte of calibration data is replaced with the receivedfirst byte of calibration data (880) and the first element of thecounter array is initialized back to one (890). The process is repeatedwith each consecutive byte of calibration data. Each data packetcontaining 1 byte of calibration data is transmitted at periodicintervals, for example every 1 minute. In other embodiments, more than 1byte, for example 2 bytes, of calibration data may be transmitted ineach data packet. In still other embodiments, less than 1 byte, forexample 4 bits, of calibration data may be transmitted in each datapacket and therefore, more than 8 data packets are needed to transmitthe entire calibration data. As such, the counter array is configuredwith enough elements to keep track of all received data bits ofcalibration data for determination of valid data transmission.

In other embodiments, if multiple types of rolling data are beingtransmitted, for example calibration data from a first and secondsensors, the receiver unit may include a counter array for each type ofrolling data. Alternatively, the receiver unit may include only a singlecounter array, wherein each element or set of elements is configured forassociation with each type of rolling data.

In further embodiments, the received rolling data may only be requiredto be within a percentage of the stored rolling data. For example, thereceived rolling data may be considered valid as long as it is ±10% orless of the stored rolling data. In other embodiments, the receivedrolling data must be within ±5% or less, for example, ±3% or ±1%, of thestored rolling data before being considered as valid.

In other embodiments, the error detection methods, devices, and systemsfor detecting error detection in the rolling (non-urgent) data of areceived data packet may also be applied to the time sensitive (urgent)data of a received data packet. As such, the time sensitive data may becompared to previously stored time sensitive data, and is only acceptedas valid if the received time sensitive data is within a physiologicallyacceptable range with respect to the stored time sensitive data. Forexample, the received time sensitive data may only be accepted as validif it is within ±30% or less, e.g. ±20%, ±10% or ±5%, of a stored timesensitive data.

In one aspect, the error detection methods described above may reducethe number of undetected errors in data packet transmissions. Forexample, the number of undetected errors in transmissions may be as fewas 50×10⁻⁶ errors per corrupted data packet or less, such as 3.3×10⁻⁶errors per corrupted data packet or less, such as 0.0025×10⁻⁶ errors percorrupted data packet.

In the manner described above, in accordance with one embodiment of thepresent disclosure, there is provided method and apparatus forseparating non-urgent type data (for example, data associated withcalibration) from urgent type data (for example, monitored analyterelated data) to be transmitted over the communication link to minimizethe potential burden or constraint on the available transmission time.More specifically, in one embodiment, non-urgent data may be separatedfrom data that is required by the communication system to be transmittedimmediately, and transmitted over the communication link together whilemaintaining a minimum transmission time window. In one embodiment, thenon-urgent data may be parsed or broken up in to a number of datasegments, and transmitted over multiple data packets. The time sensitiveimmediate data (for example, the analyte sensor data, temperature data,etc.), may be transmitted over the communication link substantially inits entirety with each data packet or transmission.

Additional description for transmission of urgent and non-urgent typedata can be found in U.S. patent application Ser. No. 11/681,133 filedMar. 1, 2007, entitled “Method and Apparatus for Providing Rolling Datain Communication Systems” and U.S. patent application Ser. No.12/130,995 filed May 30, 2008, entitled “Close Proximity CommunicationDevice and Methods”, the disclosures of each of which are incorporatedherein by reference for all purposes.

A method in one aspect may include receiving a data packet includingtime sensitive data and rolling data, comparing the received rollingdata to a previously stored corresponding rolling data, incrementing acounter when the received rolling data is within a predeterminedpercentage of the previously stored rolling data, determining if thecounter is greater than or equal to a predetermined threshold, andaccepting the received rolling data as valid.

The data packet may be received via wireless communication.

The wireless communication may be radio frequency (RF) communication.

The counter may be incremented only when the received rolling data isequal to the previously stored rolling data.

The predetermined threshold may be two.

In one embodiment, the counter is an array.

Moreover, the received rolling data may be calibration data.

Calibration data may comprise 8 bytes of data, and the rolling data ofthe data packet may be 1 byte of the 8 bytes of calibration data.

In one aspect, each byte of the calibration data may correspond to anelement of the counter array.

Incrementing the counter may comprise incrementing the correspondingelement of the counter array.

In another aspect, determining if the counter is greater than or equalto a predetermined threshold may comprise determining if all theelements of the counter array are greater than or equal to apredetermined threshold.

Each element of the array may correspond to a type of rolling data.

Incrementing the counter may comprise incrementing the correspondingelement of the counter array.

Furthermore the method may include replacing the previously storedrolling data with the received rolling data when the received rollingdata is not within the predetermined percentage of the previously storedrolling data.

In one embodiment, an apparatus may include a receiver unit configuredto receive a data packet including time sensitive data and rolling data,a memory operatively coupled to the receiver unit and configured tostore a previous corresponding rolling data, a component configured tocompare the received rolling data with the stored rolling data, and acounter configured to increment when the received rolling data is withina predetermined percentage of the stored rolling data.

The receiver unit may be a wireless receiver unit.

Furthermore, the wireless receiver unit may be a radio frequency (RF)communication receiver unit.

The counter may be configured to increment only when the receivedrolling data is equal to the stored rolling data.

The received rolling data may be accepted as valid when the counter isgreater than or equal to a predetermined threshold.

In one aspect, the predetermined threshold may be two.

In one embodiment, the counter may be an array.

The received rolling data may be calibration data.

Calibration data may comprise 8 bytes of data, and the rolling data ofthe data packet may be 1 byte of the 8 bytes of calibration data.

Each byte of the calibration data may correspond to an element of thecounter array.

Moreover, the corresponding element of the counter array may beconfigured to increment when the received rolling data is within apredetermined percentage of the stored rolling data.

The received rolling data may be accepted as valid when all the elementsof the counter array are greater than or equal to a predeterminedthreshold.

One aspect may further include replacing the stored rolling data in thememory with the received rolling data when the received rolling data isnot within the predetermined percentage of the previously stored rollingdata.

In one embodiment, a data monitoring and management system may include acommunication link, a transmitter operatively coupled to thecommunication link, the transmitter configured to transmit a data packetincluding time sensitive data and rolling data, and a receiveroperatively coupled to the communication link, the receiver configuredto receive the transmitted data packet, wherein the receiver isconfigured to determine if the received rolling data is valid bycomparing the received rolling data to a previously stored correspondingrolling data, incrementing a counter when the received rolling data iswithin a predetermined percentage of the previously stored rolling data,and determining if the counter is greater than or equal to apredetermined threshold.

In one aspect, the communication link may be a wireless communicationlink.

In another aspect, the wireless communication link may be a radiofrequency (RF) communication link.

Various other modifications and alterations in the structure and methodof operation of this invention will be apparent to those skilled in theart without departing from the scope and spirit of the invention.Although the invention has been described in connection with specificpreferred embodiments, it should be understood that the invention asclaimed should not be unduly limited to such specific embodiments. It isintended that the following claims define the scope of the presentdisclosure and that structures and methods within the scope of theseclaims and their equivalents be covered thereby.

1. A method, comprising: receiving a data packet including time sensitive data and rolling data; comparing the received rolling data to a previously stored corresponding rolling data; incrementing a counter when the received rolling data is within a predetermined percentage of the previously stored rolling data; determining if the counter is greater than or equal to a predetermined threshold; and accepting the received rolling data as valid.
 2. The method of claim 1, wherein the data packet is received via wireless communication.
 3. The method of claim 2, wherein the wireless communication is radio frequency (RF) communication.
 4. The method of claim 1, wherein the counter is incremented only when the received rolling data is equal to the previously stored rolling data.
 5. The method of claim 1, wherein the predetermined threshold is two.
 6. The method of claim 1, wherein the counter is an array.
 7. The method of claim 5, wherein the received rolling data is calibration data.
 8. The method of claim 7, wherein calibration data comprises 8 bytes of data, and the rolling data of the data packet is 1 byte of the 8 bytes of calibration data.
 9. The method of claim 8, wherein each byte of the calibration data corresponds to an element of the counter array.
 10. The method of claim 9, wherein incrementing the counter comprises incrementing the corresponding element of the counter array.
 11. The method of claim 10, wherein determining if the counter is greater than or equal to a predetermined threshold comprises determining if all the elements of the counter array are greater than or equal to a predetermined threshold.
 12. The method of claim 11, wherein the predetermined threshold is two.
 13. The method of claim 6, wherein each element of the array corresponds to a type of rolling data.
 14. The method of claim 13, wherein incrementing the counter comprises incrementing the corresponding element of the counter array.
 15. The method of claim 1, further comprising replacing the previously stored rolling data with the received rolling data when the received rolling data is not within the predetermined percentage of the previously stored rolling data.
 16. An apparatus, comprising: a receiver unit configured to receive a data packet including time sensitive data and rolling data; a memory operatively coupled to the receiver unit and configured to store a previous corresponding rolling data; a component configured to compare the received rolling data with the stored rolling data; and a counter configured to increment when the received rolling data is within a predetermined percentage of the stored rolling data.
 17. The apparatus of claim 16, wherein the receiver unit is a wireless receiver unit.
 18. The apparatus of claim 17, wherein the wireless receiver unit is a radio frequency (RF) communication receiver unit.
 19. The apparatus of claim 16, wherein the counter is configured to increment only when the received rolling data is equal to the stored rolling data.
 20. The apparatus of claim 16, wherein the received rolling data is accepted as valid when the counter is greater than or equal to a predetermined threshold.
 21. The apparatus of claim 20, wherein the predetermined threshold is two.
 22. The apparatus of claim 16, wherein the counter is an array.
 23. The apparatus of claim 22, wherein the received rolling data is calibration data.
 24. The apparatus of claim 23, wherein calibration data comprises 8 bytes of data, and the rolling data of the data packet is 1 byte of the 8 bytes of calibration data.
 25. The apparatus of claim 24, wherein each byte of the calibration data corresponds to an element of the counter array.
 26. The apparatus of claim 25, wherein the corresponding element of the counter array is configured to increment when the received rolling data is within a predetermined percentage of the stored rolling data.
 27. The apparatus of claim 26, wherein the received rolling data is accepted as valid when all the elements of the counter array are greater than or equal to a predetermined threshold.
 28. The apparatus of claim 16, further comprising replacing the stored rolling data in the memory with the received rolling data when the received rolling data is not within the predetermined percentage of the previously stored rolling data.
 29. A data monitoring and management system, comprising: a communication link; a transmitter operatively coupled to the communication link, the transmitter configured to transmit a data packet including time sensitive data and rolling data; and a receiver operatively coupled to the communication link, the receiver configured to receive the transmitted data packet; wherein the receiver is configured to determine if the received rolling data is valid by comparing the received rolling data to a previously stored corresponding rolling data, incrementing a counter when the received rolling data is within a predetermined percentage of the previously stored rolling data, and determining if the counter is greater than or equal to a predetermined threshold.
 30. The system of claim 29, wherein the communication link is a wireless communication link.
 31. The system of claim 30, wherein the wireless communication link is a radio frequency (RF) communication link. 